Patent GB-1385827-A (GB)
Title: Cylinder lock and key
IPC: B60R25/021
Filed: 1973-08-06
Abstract: 1385827 Steering column locks C O NEALE 6 Aug 1973 [28 Aug 1972] 37213/73 Heading B7J [Also in Division E2] In a motor-vehicle steering-wheel cylinder lock and key, the key 25 includes an extension 26 extending substantially transversely to the longitudinal axis of the key in a plane parallel to the side faces of the key, the extension projecting, in use, into an axial groove 11 in the lock cylinder housing 1 and being arranged to project from the keyway 9 beyond the lock core 3 to enter a space R beyond the groove when the key has been pushed fully into the keyway of the lock cylinder and co-operate with a control mechanism in the cylinder housing to control additional functions of the lock. As shown, a groove 11 in the lock housing 1 is aligned, in the unlocked position, with the keyway 9 in the core 3, and a control member 12 is biased by a spring 20 to rotate about a pin 14. Upon insertion of the key 25 into the lock, position I, Fig. 4, the extension 26 of the key rides over the extension 17 of the member 12 and becomes disposed in the space R at the end face 6 of the housing 1 whereby upon rotation of the core and associated locking member 7 to the locking position II withdrawal of the key is prevented. Return of the core 3 to the position I re-aligns the groove 11 and keyway 9 and during withdrawal of the key the extension 26 thereof engages the shoulder 18 of the member 12 to entrain the latter so that the incline 19 of the member engages the incline 23 of the lock body whereby the member 12 is pivoted to disengage the extension 26 and shoulder 18 to permit complete withdrawal of the key; the member 12 is returned by the spring 20 to the position shown in Fig. 1. In modifications, (a) two rows of staggered, non-rotatable, tumbler pins are disposed transversely to the plane of the keyway 9 and are operated by a flat-key having depressions on one face thereof and an extension 26 forming a step with one face of the key, (b) the housing 1<SP>1</SP> is received in a steering-wheel lock housing and the lock operates an ignition and starting switch and a transverse lock bolt 36 axially movable to the locking position by a spring 35; the control member 12<SP>1</SP> is initially retained in the position shown in chain line by the abutment thereof with the tail 37 of the bolt 36 but upon insertion of the key 25 into the lock and rotation of the lock core 3 to withdraw the bolt 36 from a locking position and by means of a shaft 40 on an eccentric 33 connected to the core, a groove 45 in the bolt tail 37 is brought into alignment with the projection 44 of the control member when the latter is displaced by the spring 20 into the groove to hold the bolt 36 in an unlocked position, (c) a steering wheel lock includes an axially movable locking bolt 46 provided with a hook end 48 which engages a cam 33<SP>1</SP> whereby rotation of the core 3 withdraws the bolt against the bias of a spring 35<SP>1</SP>. The bolt is held in the withdrawn position shown by a spring-loaded, U-shaped member engaging in a recess 56 of the bolt, that member, upon withdrawal of the key 25 with consequent entraining of the control member 1211, being disengaged from the recess by a head 53 of the control member whereby the bolt is moved to the locking position thereof by the spring 35<SP>1</SP>, the hook 48 of the bolt moving over a spring- loaded latch 64 of the cam 33<SP>1</SP>; the control member is biased forwardly by a spring 20<SP>1</SP> and inwardly by a spring-loaded pin 51 slidable in an axial recess 52 in the housing 47, and (d) the axially movable lock bolt 46 carries a spring- loaded holding member 66 which engages in recesses 68 to hold the bolt in a retracted position, the member, upon withdrawal of the key 25, being disengaged from the recesses by the control member 12<SP>111</SP> to allow the bolt to move to the locking position thereof; latch 72 engages behind a plate 74 carried by the core 3.